The present invention relates to synthetic doors, windows and panels, to methods of making them and to precursors therefor.
Doors, windows and panels have traditionally been made from wood, which may be glazed or unglazed. However, unless specially treated, wood can warp if exposed to changes in temperature and/or humidity. This can be disadvantageous aesthetically and can also lead to difficulties in opening and closing the doors, windows and partitions. The latter are particular problems in the light of modern building safety regulations, where warped doors, windows and panels can constitute a fire hazard. Furthermore, wood can be relatively expensive to obtain and there are major environmental concerns in respect of the use of certain types of wood.
Over the last few decades there has therefore been a trend towards providing artificial doors, panels and windows. One type of artificial door is a moulded door. Moulded doors can be formed by a number of different methods.
In one method two preformed skins are provided by vacuum forming in complementarily shaped moulds and are then secured to opposite sides of a frame, prior to injecting a foam into a cavity located between the skins. The foam acts as a filler and can assist in providing increased improved rigidity and insulation the door. The door can then be removed from the press and finished as appropriate.
However, although this method can be effective, it is not always reliable. This is because the curing of foam and the filling of the cavity is difficult to control accurately. Furthermore, the rheological properties of the curing foam can be adversely affected by wire mesh reinforcements, which are often provided between the skins in order to strengthen the resultant product.
Another method is to provide a preformed foam, which may be held within a frame, and to adhere first and second skins to opposing faces of the foam and/or frame. This is generally achieved by first forming a “sandwich” comprising the skins as outer layers and the foam (optionally within a frame) as an inner layer with adhesive applied to inner surfaces of the skins and then applying heat and pressure so that the components are laminated together.
In both of the foregoing methods two skins are generally provided from a moulding company and then assembled into a door, window or panel in a workshop by a different company. Following lamination in the workshop a finishing process is required, which requires skilled labour. For example the door, window or panel comprising the two skins and foam interior may be shaped, trimmed, routed, drilled, or painted; one or more glazing panels, handles, locks, etc. may be added; or it may be prepared to receive such articles (e.g. by drilling appropriate holes, cutting out recesses/apertures, planing, etc.)